Reliability long-term

The proper compressor selection for the application is probably the most important single factor to achieving long-term reliable operation. For all the factors that make the centrifugal one of the most reliable compressors, a misapplication will negate these most dramatically. 

An additional feature of chemometrics that is appealing to process analytical applications is the use of qualitative models to detect and characterize faults in the analyzer system (calibration, instrument, sampling interface, and sampling systems), sample chemistry, and process dynamics. Such faults can be used to trigger preventive maintenance, and to troubleshoot- thus supporting the long-term reliability of the analyzer system. Specihc examples of such fault detection are given in references [15-16]. 

Mechanical Properties. Most of electronic IC devices are very fragile. They need strong mechanical protection from the encapsulant to retain their long-term reliability. Encapsulant must provide mechanical protection but still maintain good temperature-cycle and thermal-shock testing, which are part of the routine reliability testing of the embedding electronics. 

There are several key factors to the success of the long-term reliability and viability of a PA system. Based on experience, it is necessary to have an on-site owner central to facilitating performance monitoring, maintenance and updating of the system to obtain long-term value out of a PA system. Overall, production operations are responsible for a large number of systems and equipment. By assigning one or two people as owners of the PA system, the... 

Reliability and serviceability FTIR instruments have not been known for long-term reliability, based on lab experience. Attention must be paid to optical stability, and the reliability of key components, such as optics (non-hygroscopic preferred), electronics, lasers, and sources. If a component has to be replaced, then a non-specialist technician must be able to perform the task. 

Process analytical applications differ from laboratory analytical applications in that the analyzer hardware and software are in a more hostile environment, the maintenance and operations personnel in the analyzer area are typically not trained like lab technicians, and the purpose of the analyzer is most often for rapid process control rather than troubleshooting. As a result, process analytical applications tend to focus more on automation, minimization of maintenance, and long-term reliability. In this more pragmatic context, the instrument specialization function of chemometrics is used even more exclusively than the information extraction function. 

Aside from univariate linear regression models, inverse MLR models are probably the simplest types of models to construct for a process analytical application. Simplicity is of very high value in PAC, where ease of automation and long-term reliability are critical. Another advantage of MLR models is that they are rather easy to communicate to the customers of the process analytical technology, since each individual X-variable used in the equation refers to a single wavelength (in the case of NIR) that can often be related to a specific chemical or physical property of the process sample. 

Van der Biest O, Weber C (1994) Influence of Oxidation on Long Term Reliability of Silicon Nitride. In Nickel KG (ed) Corrosion of Advanced Ceramics - Measurement and Modelling. Kluwer Academic Publishers, Dordrecht, p 453... 

The developments in the field of photo-initiated AOPs over the last decade undoubtedly indicate their large-scale feasibility with some restrictions concerning the costs of these processes as stand-alone systems, the long-term reliability of the system components (lamps etc.) and the possible formation of undesirable byproducts in some cases. However, photo-initiated AOPs have many similarities with nature s own self-repair mechanisms of natural pollution. Many of them can be adapted, in particular solar AOPs, for use in developing countries. 

In many cases, the protection provided by a simple barrier coating such as RTV silicone will be suflScient to ensure long-term reliability of the device. Small, ceramic-based, hybrid ICs designed to be inserted into a PWB are often protected in this manner. However, for other applications, additional protection is required to provide impact and shock resistance (RTV silicones are very soft and offer little mechanical protection), better environmental protection, and a well-defined structure for subsequent assembly and handling. Such protection is provided by embedment in a hard plastic by transfer or injection molding as shown in Figure 1.6. The molding process leaves two parallel rows of pins exposed for subsequent connection to the PWB. 

Where the feedstock has an intrinsic value c.g. it can be used as a fuel in other processes (and, thus, there is some competition between procurers), the independent assessors of the project will require to see evidence of its long term, reliable, delivery in sufficient quantity to satisfy the needs of the project Some measure of price stability will be necessary, for example by linking fiiel purchase price to recognized and appropriate cost indices. 

In the assessment of the German NAP, the diverse uncertainties for the operators are again and again put forward as a central point of criticism and both clear and straightforward specifications are required, as well as long-term reliability. At the same time, diverse new special provisions are being demanded by many actors. The simplicity, transparency and calculability of the allocation rules, both for the operator and for the political decision-makers, should take on a special role with regard to future NAPs. 

---